title: Finite-size limitations on Quality factor of guided resonance modes in 2D photonic crystals.
abstract: High-Q guided resonance modes in two-dimensional photonic crystals, enable high field intensity in small volumes that can be exploited to realize high performance sensors. We show through simulations and experiments how the Q-factor of guided resonance modes varies with the size of the photonic crystal, and that this variation is due to loss caused by scattering of in-plane propagating modes at the lattice boundary and coupling of incident light to fully guided modes that exist in the homogeneous slab outside the lattice boundary. A photonic crystal with reflecting boundaries, realized by Bragg mirrors with a band gap for in-plane propagating modes, has been designed to suppress these edge effects. The new design represents a way around the fundamental limitation on Q-factors for guided resonances in finite photonic crystals. Results are presented for both simulated and fabricated structures.
authors.forename: Jon Olav
authors.initials: JO
authors.lastname: Grepstad
authors.forename: Martin M
authors.initials: MM
authors.lastname: Greve
authors.forename: Bodil
authors.initials: B
authors.lastname: Holst
authors.forename: Ib-Rune
authors.initials: IR
authors.lastname: Johansen
authors.forename: Olav
authors.initials: O
authors.lastname: Solgaard
authors.forename: Aasmund
authors.initials: A
authors.lastname: Sudbø